1. Field of the Invention
This invention relates to a brake lever, and more particularly to a hydraulic brake that includes a brake lever.
2. Description of the Related Art
Referring to FIG. 1, a first conventional hydraulic brake disclosed in U.S. Pat. No. 5,813,501 includes a body 1, a piston 101 disposed within the body 1, and a brake lever 102 disposed pivotally on the body 1. By rotating a setscrew 103 on the brake lever 102, a reach (i.e., the distance between the brake lever 102 and a bicycle handlebar) can be adjusted. By rotating an adjustment screw 104 on the brake lever 102, a starting position of the piston 101 can be adjusted.
During adjustment of the reach or the starting position, operation of each of the setscrew 103 and the adjustment screw 104 results in rotation of the other one of setscrew 103 and the adjustment screw 104. Hence, readjustment of the setscrew 103 and the adjustment screw 104 is required. Further, since the ratio of the distance between the setscrew 103 and the brake lever 102 to that between the adjustment screw 104 and the brake lever 102 is 1:3, a relatively large change of the starting position occurs when the reach is adjusted.
Referring to FIGS. 2 and 3, a second conventional hydraulic brake disclosed in U.S. Pat. No. 6,804,961 includes a body 2, a piston 201 disposed within the body 2, a brake lever 202 disposed pivotally on the body 2, a hex spacer 3 fitted partially into the piston 201 and having two retaining slots 301, an adjustment knob 4 engaging threadably the body 2 and formed with a hex hole permitting the hex spacer 3 to be fitted thereinto, a male pushrod 5 extending through the adjustment knob 4, a female pushrod 6 engaging threadably the male pushrod 5, and a socket insert 7 disposed removably between the female pushrod 6 and the brake lever 202. The male pushrod 5 includes two posts 501 engaging respectively the retaining slots 301 in the hex spacer 3, and an externally threaded shaft 502. The female pushrod 6 includes an internally threaded cylinder 601 engaging the externally threaded shaft 502, a ball head 602, and two posts 603. The socket insert 7 includes two slots 701 engaging respectively the posts 603, and two post 702 connected removably to the brake lever 202. As such, by rotating the adjustment knob 4, a starting position of the piston 201 can be adjusted to thereby vary a dead band distance between a seal 203 and a port 204. When the adjustment knob 4 is operated to rotate together with the hex spacer 3, the threading movement of the male pushrod 5 relative to the female pushrod 6 occurs to change the total length of the male and female pushrods 5, 6 to thereby maintain the reach of the brake lever 202 unchanged. However, such a hydraulic brake is complicated in construction.
Furthermore, to adjust the reach, the brake lever 202 is first pushed away from the body 2 to remove the socket insert 7 from the ball head 602 of the female pushrod 6. Next, the male pushrod 5 is threaded relative to the female pushrod 6. Finally, the socket insert 7 is mounted back onto the ball head 602. Consequently, it is difficult to adjust the reach.